Conduit-box.



P. J. HURST.

GONDUIT BOX* APPLlGATloN FILED 001.1s,1911.

Patented Aug. 12, 1913 (la t fil FRANCIS J. HRST, OF DENVER, COLOEADO.

CONDUIT-BOX.

Specification of Letters Patent.

Patented Ang@ 15.2,

Application filed Getolaer 13,1911. Serial o. itnli'.

To fd/ fx1/om ZZ may concern;

vllc it known that l, FRANCIS J. HURST, a citizen oi the United States, residing at the city and county of Denver and State oit Colorado, have invented certain new and nsei'ul lu'iprovelnents in Conduit-Boxes; and l do declare the following to be afulhclear, and exact description or' the invention, such as will enable others skilled in the art to which it apg'iertainsto make and use the saine, reference being had to the accompanyin g drawings. and to the characters of reference marked thereon, which form a part ot' this spociiication.

My invention relates to improvements in conduit boxes or boxes adapted for holding switches, cut-outs, fuse-blocks and all similar apparatus used in connection with electrical wiring.

The object ot lny improvement is to make it practicable to form the openings in boxes ot this character of uniform size and adapted to receive the largest conduit, my im provenient consisting,y in providing means whereby these openings may be reduced to conform to all sizes of conduits from the largest to the smallest. This is accomplished by applying` plates to the opposite sides of the box where the openings are located, the said plates being suitably secured in place, either by screwing them upon'the endet the conduit, which is threaded for the purpose, the plates being applied to the opposite sides of the box, or by applying the plates to the conduit, their' openings being plain or unthreaded, and securing them by means of nuts. In either event, the invention is thoroughly eiiicient.

Having briey outlined my improved construction, l will proceed to describe th` same in detail, reference being made to t e ac-` companying drawing, in which is illustratedl an embodiment thereof.

In this drawimgg;: Figure 1l illustrates a conduit box with the cover removed, several of the openingsbeing equipped with my improvement. Fig. 2 is a fragmentary sectional detail view, illustrating the improve.- ment shown on a larger scale. Fig. 3 is aA similar view, showing a slightly modified torni of construction. V

The saxnevreference charactersindicate the saine parts in all the views.

adapted to contain any of the ordinary con;- duits or conductors employed in connecti'on 'tothe'forceapplied in screwing the with electrical wiring. The openings o ot this box are made ont uniform size, and are large enough 'to receive conduits of inanimum size.

My improvement consists' in applying,l plates 7 and 8 to the 'opposite sides ot the box, where the openings ti are located, the plates being large enough to overlap the wall 9 of the box around the said openings, the openings 10 in the plates being o such size vas to contorni to the size of the conduit l2 to be connected with the box.' As illustrated in Figi. 2, these plates "Z and 8 are threaded to screw upon the threaded end 75- 13 of the conduit, one of the plates lo applied to the box on each side and tiht ened by screwing them the proper pol tion. Beyond the outermost plate *Z a tin bushing le is screwed upon the cond-.uit the y said bushing having an opening lf3 through which the wires7 carried by the conduit, may pass to the iinerior of tia-eben.,

In the form ot construction shown in 3, the plates 7 and 8 have plain or untli ed openings 1G, but are applied to 9 of the box in the saine to say, the outer edgesoit the plates c o the wall around the openingr n torni of construct-ion, the two plate locked in place by means or nuts i? and iti, the nuts 17 being app. ed to the outer sur. A tace of the plate 8, while the plied to the inner sui. 'i where-hy the two plates are securel to the box. Beyond the nut bushing 14C is applien.

The plates 7 and 8 prefere inwardly, whereby the portion oit y 8 conforming to the opening '6 o'n o si enters the said opening, either wholly or partially filling the same, while the plate is odset inthe saine direction., norniz. y

vleaving airspace 19 between'the twopiates, ,This oset feature maires :at practicable to l0@ clamp theV plates more tightly in position, and also prevents the possibie shitting ot the plates upon the wall 'ot' the box, since the offsetpart or' the plate 8, ex ending` into the opening, prevents later-ai movement.

lt will be understood that, in 'View of the `fact that the plates 7 andA 8 are slightly `tl-exible, .and in view of the space 19 sepal 'rating the two pistes. @and o, the inner Let the numeral 5 designato a conduit born. i

portion of the plate 7 will yield more or upon thefvcondnit, as shown-in Fig 1 clamping llie saine thereon uy means oi1 nul; 16, aS shown in lli`ig'. 3, lling securing the outer edges of tlie plate 7 .so tightly lo the wall of the box lliat the joint is pracl'r cally sealed against -tlie poesilile 'entrance of moisture or foreign inal'lier or substances of any kind.

From die foregoing description, tlie aclvantages oil' niy improvement will be readily understoml. l'l'creto'fore, so 'lar as l ain aware, it llas been necessary to inake the openings in liioxea of this character conform insizc lo lie various sizes of conduits einployed tlie'ewilli. By the use of niy irnproved constructiiim, it becomes practicable to make ille opening?l in all boxes of uniorni size, VMT-olf the maximum size required orv tlie largest cmiduit. lV lien thi. iS done by the use of my improvement, these openings may be reduced lo conform Lo the sizes ol the 'vazione conduils withoutany change whatever .in the body of tlie box.

Leases?? llaying illus decrilicd iny invention, what l claiin :P- v 'l`lie combination willi a'liox having rela- 'tively large openings to receive 'conduits for holding,` electrical conductors, reducing plaies applied lo llie opposite Surfaces of the box around ille openings, tl'ie central porl'ious ol' said plaies being in planes parallel with but olle-et from the rims thereof,

the ellis-et portion of the oulor plate extending inwardly lo enter tlie box opening llievollsct por-lion oiI the inner plate extend4 ing in the saine direction, and Suitable inca for Securing the plaies in place, 'for ieee-i Aram-rere- @oer gs, and 

